A recital by Icelandic pianist Víkingur Ólafsson at Carnegie Hall. A Finnish conductor, Klaus Mäkelä, becoming the Chicago Symphony Orchestra’s next music director while already drawing major attention in the U.S. A full Carnegie Hall season honoring Estonian composer Arvo Pärt. The Metropolitan Opera staging Kaija Saariaho’s Innocence. Taken separately, these might look like isolated success stories. Together, they suggest something larger: Nordic and Baltic classical artists are not just appearing in North America’s top institutions.